Klippel-Feil Syndrome: Causes, Classification, Symptoms, Signs, Diagnosis, Treatment

This is a congenital disorder of the cervical spine in which there is fusion of two or more vertebrae. People from Klippel-Feil syndrome tend to have a short neck and their neck motion is significantly restricted. There may also be presence of pain in the neck.

• Abnormal Bone Fusion- Klippel-Feil Syndrome is a form of a disorder of the bones in which there is abnormal fusion of two or vertebrae of the cervical spine, which is present since birth.
• Characteristic Features-There are three characteristic features of Klippel-Feil Syndrome. Majority of the affected individuals have at least two of the three features mentioned below. The three characteristics features are as follows-
  1. Short neck
  2. Low hairline behind the neck
  3. Extremely limited range of motion of the cervical spine.
• Range of Motion- People with Klippel-Feil Syndrome have limited range of motion of the cervical spine due to abnormal fusion of the vertebrae.
• Radicular Pain- Patient suffers with severe pain. Pain is often caused by pinch nerve at spinal foramina. Because of this abnormal fusion of the vertebrae of the cervical spine, the nerves of the neck or back may also be affected. As the disease progresses, the affected individuals tend to develop spinal stenosis as well compressing and damaging the spinal cord.
• Motor Nerve Hyperactivity- In rare cases, there may be abnormal uncontrollable movements of the arms as well.
• Scoliosis- People affected with Klippel-Feil Syndrome also later on in their life develop scoliosis, a medical condition in which there is abnormal curvature of the spine.
• Visceral Deformity- The syndrome may be associated with multiple visceral diseases involving heart,² kidneys, skeletal system, vertebral artery anomaly³ and neural tube.
• Sprengel Deformity- Some affected individuals may also have a condition called Sprengel deformity in which there is poor development of the shoulders resulting in abnormal elevation of the scapula.

• Klippel-Feil Syndrome is said to be caused due to mutations in genes GDF6 and GDF3.
• The function of these genes is to instruct cells into making proteins to regulate growth and maturation of the bones and cartilages in the body.
• The GDF6 protein is required for formation of bones in the limbs, spine, skull, chest, and ribs. While the exact role of the GDF3 protein is unclear, it is also known to be involved in development of bones and cartilages.
• The mutations of the GDF6 and GDF3 genes result in reduction of functional protein causing Klippel-Feil Syndrome.

Type I: The first cervical vertebrae is also known as atlas is fused with occipital bone and the condition is known as occipitalization of atlas. Type I is also associated with fusion of C2-C3 vertebra. Severe malformation may result in narrowing of spinal canal and compression of spinal cord and brainstem.

Type II: In this type, there is fusion of the vertebrae below C2 level along with abnormality of the occipitocervical junction.

Type III: In this type, there is a single interspace between two fused segments and the motion of the cervical spine is centered at this solitary open articulation. This can lead to spine instability or osteoarthritis.

• The mild type of disease is often asymptomatic.
• The diagnosis is incidental when CAT scan or MRI of cervical spine is performed to evaluate other diseases than spine.

• Radicular Pain-
  • Common symptom originates from disc, facet joint or pinch nerve. Pain during early stages originates from paravertebral muscles, disc or facet joint.
  • The abnormal skeletal structure in neck causes disc, facet join or paravertebral muscle pain.
  • During later stage, if disease becomes severe and results in spinal stenosis then patient may describe symptoms suggesting pinch nerve followed by radicular pain.
  • Radicular pain radiates along the nerve pathways in upper extremities.
• Tingling, Numbness and Weakness-
  • These symptoms suggest either nerve is pinched at the foramina or spinal canal.
  • Patient may complaint of these symptoms in upper extremity suggesting nerve is pinched at the foramina and may be one to three levels are affected.
  • Bilateral symptoms involving upper and lower extremity suggest possible narrowing of spinal canal, also known as spinal stenosis.
  • Spinal stenosis may constrict spinal cord resulting in symptoms in all four extremities.⁴
• Shortness of Breath
  • Klippel-Feil Syndrome may be associated with alveolar disease or bronchial hypertrophy resulting in shortness of breath or dyspnea.
• Palpitation
  • The syndrome may be associated with abnormal cardiac conduction system causing irregular heartbeats and palpitation.

• General Examination-
  • Extremely short neck
  • Low hairline behind the back of head
• Skeletal Examination-
  • Limited range of motion of the cervical spine
  • Short stature
  • Scoliosis
  • Spina bifida
  • Cleft Palate.
• Visceral Examination-
  • Kidney Dysfunction- Higher albumin excretion in urine, high BUN or creatinine
  • Respiratory Difficulties- Wheezing
  • Vascular Examination- Vertebral artery anomaly. ³
  • Cardiac Abnormalities- Irregular heart beats and complete heart block.²
  • Gastrointestinal System- Duodenal web and rectal abnormalities were observed with K-F syndrome.⁵

Urine Examination- Increased albumen in urine and decreased urine volume

Blood Examination- Increased BUN and creatinine

Radiological Studies-

• X-Ray, MRI and CT Scan-
  • Spinal vertebral fusion observed between cervical vertebrae C2 to C5.
  • Scoliosis
  • Spina Bifida
  • Atlanto-axial dislocation ³

Klippel–Feil Syndrome is usually treated symptomatically.

• NSAIDs
• Opioids
• Muscle Relaxants

• Cervical Vertebral Abnormalities-
  • Surgical procedure may also be done to correct craniocervical instability and remove the pressure over the spinal cord.
  • Cervical Disc Arthroplasty is done to correct fusion by using the Bryan Cervical Disc Prosthesis.
  • Total Disc Replacement is an alternative procedure performed to correct foraminal stenosis. Procedure virtually eliminates the pain and discomfort.
  • When Arthroplasty does not provide total relief then as a last measure arthrodesis procedure is done for pain relief from Klippel-Feil Syndrome.
• Scoliosis-
  • The corrective procedure is performed if patient has advanced symptoms suggesting numbness and weakness in upper and lower extremities.
  • Surgical procedures may also include spinal surgery to relieve pressure on the spinal cord.

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